Thread rolling



' April 1, 1947- J. w. BATCHELDER 7 2,418,217

THREAD ROLLING Filed Feb. 2:5, 1944 I I I James zll lz z f zt ier;

BY M M ATT.

Patented Apr, 1,1941

UNITED STATES PATENT OFFICE a.

James w. Batchelder, Alstead, N. a, aaalg'nor to Jones & Lamson Machine Company, Springiield, Vt., a corporation of Vermont Application February 23, 1944, Serial No. 523,549,

The present invention relates to the art of thread rolling, and more particularly to thread rolling machinery employing a plurality of circular thread rolling dies for rolling a work blank therebetween to produce threads thereon. a It is a principal object of this invention to simpliiy the operation of phasing the circular thread rolling dies relative to one another so that the threads produced on the work at the point of thread rolling contact will be properly formed in relation to the preceding threads rolled on the work as the dies and work are rotated.

It is also an object oi. this invention to provide a thread rolling die and spindle construction which will facilitate the quick application and interchangeability of thread rollinrdies to the spindle of a multiple spindle thread rolling machine and which will assure accurate phase relationship between. threads oi the thread rolling dies thus applied. I y

In accordance with thepresent known principles of thread rolling machines wherein circular thread rolling dies are used to roll threads on a work blank positioned at a point between the peripheries of the dies, it has'been necessary to disconnect at least one of the spindles on which a thread rolling die is mounted from the gearing and transmission mechanism connecting the spindles together in order' that the angular position of one of the thread rolling dies may be adjusted relative to the' others so that the threads on the periphery of the dies at the point of thread rolling contact will be in proper phaserelation with each other. Alternatively, the dies may be moved axially of each other to obtain the proper phase relation. phase relationship may be.

tore, contemplates the provision of keyways in the spindle bore of the'circular thread rolling dies which will cooperate with key seats and keys on the spindles oi the thread rolling machine to insure that the thread rolling die is always placed on the spindle in the same desired angular relationship. Since the spindles are permanently geared together in constant ratio with the keyseats on the spindles in a predetermined relation to each other the accurate phasing oi the thread rolling dies will be assured after each application oi the dies to the spindles.

It is also an object oi this invention to provide a thread rolling die and spindle construction having means for determining and accurately phasing the thread roliingdies at the time of application of the dies to the spindle which will be consistently accurate to such an extent as to always assure a'much higher degree of. precision thread rolling than heretofore obtained when interchangeably applying the dies to the spindles.

It is a still further object of this invention to provide a circular thread rolling die with a plurality of keyways which will enable the die to be interchangeably applied to any 0! the spindles of a circular thread rolling machine employing explained by observing that as the work rotates past the point of thread rolling contact during the thread rolling proess, the groove previously formed on the work by the thread rolling die must line up exactly with the thread of the die at the succeeding point of thread rolling contact on the work. Varying the angular or axial position of one die relative to another to bring the dies to this relationship is called phasing. The present type of thread rolling machines which are providedwith members capable of disconnection for the purpose of revolving one die spindie with relation to another so as to phase the dies are not entirely satisfactory since this operation mustbe conducted on a cut and try basis, and it is therefore, difllcult to obtain in this manner the exact phasing of the dies required for precision thread rolling. This invention therethe principle of incommensurable angle'thread rolling and which will assure the accurate phasing of the dies thus applied.

Further objects and advantages will be readily apparent by referring to the following specification and drawings in which:

Figure 1 is a transverse section through a pin-- rality of thread rolling dies and spindles embodying the principle of this invention, and also showing'in transverse section a pair of work blanks spindles of a thread rolling machine embodying the principle of this invention and showing the gearing for permanently connecting the spindles together in a predetermined and unvarying angular relationship, and also showing means for varying the distance between the centers of the thread rolling spindles for rolling diflerent diameter work blanks.

on each die respectively A, A and A".

Figure 4 is a plan view of the circular thread rolling die or this invention and showing in dotted lines the keyway located in a predetermined relation to a point on the thread which may be the thread start on any other predetermined point.

Referring to Figure l of the drawings, the inmention is shown as applied to a three spindle circular die thread rolling machine in which a pair of work blanks are simultaneously rolled with their work centers positioned at a point beneath the common plane of the spindle axes. I'his'type of thread rolling which is known as incommenin the die bores for determining this phase relasurable angle thread rolling, has certain advanl2, l3, and H at the thread rolling contact point |5, I6, l1 and |8'respectively. The thread rolling dies l2, l3, and 14 are located on thread rolling spindles I9, 20, and 2| respectively. The spindles I9, 20, and 2| arev provided with keyseats 22, 23, and 24. At the time of the assembly of the machine these spindles whose axes are all located in a common plane are angularly-positioned so that their keyseats are all located in parallel axial planes of the spindle axes as shown by Figure 1.

The spindles are then permanently geared together by any suitable gearing suchas that shown by Figure 3 of thedrawings wherein a drive shaft, 25, is provided with worms 26, 21, and 28 in assotion must be diiierently angularly located for each spindle, necessitating a number of different keyways equal to the number oi spindles of the machine. The keyway 4| is located beneath the thread start point A, A, or A" and in the axial plane intersecting said thread start point. With the keyway 4| located as described above, it is necessary to locate the other keyways 40 and 42 intheir proper angular positions relative to keyway 4| so that the dies may be interchangeably mounted on any or the three spindles of the incommensurable angle thread rolling machine being described. To locate the keyways 40 and 42 in their proper angular position relative to keyway 4|, the following formula is used, wherein the angle in'degrees is the incommensura-ble angle of thread rolling, or what may be otherwise described as the angular displacement of the work center from the common plane of the spindle axis, wherein the angle Y is equal to theang'ul'ar displacement in degrees of the keyways 40' and 42 from the .keyway 4|, and wherein S is equal to the i ery of the thread rolling die.

ciation with worm gears 29, 36 and 3| which are keyed to the thread rolling spindles I9, 20, and 2| respectively. The worms 26 and 26am slidably keyed to the main drive shaft by means of splines 32 and 33 thuspermitting longitudinal movement of the worms 26 and 28 along the shaft 25 so that the spindles l9 and 2| may be moved apart relative to the spindle 26 as will be more fully de-- vided with a plurality of thread starts on their threaded peripheries, one of each of which thread starts may be designated by the reference points In this case, the work blanks l6 and II will have produced, by the rolling process on their peripheries, a thread having a single thread start designated by the points B and B respectively, and it should be mentioned that the number of thread starts on the circular thread rolling dies is not critical and may be any number so long as they are an integral'multiple of the number of thread starts to be produced on the work. To employ the principle oi' this invention in connection with the incommensurableangle thread rolling being discussed, each of the thread rolling dies must be provided with a number of keyways 40, 4| and 42, identically located on each thread rolling die.

Because of the fact that the work centers. arev beneath th common plane of the spindle axes,-

. 2X Y= 2X +73- Thus it will be seen that the angular displacement in degrees of the keyways relative to each other is a function of. the incommensurable angle in degrees and the number of thread starts on the dies. 7

With the keyways 40, 4| and 42 thus located,

it is possible to interchange any die |2, |3 or M to anyof the three spindles shown in Figure 1 by merely observing that the correct keyway in the die bore is in alignment with the keyseat on the spindle to which it is to be applied and if this is done, the dies will always be in proper phase relation with each other. It should be understood that the invention being described is in connection with a circular thread rolling machine in which all of the dies rot-ate in the same direction.

In employing the principle of this invention on a three spindle incommensurable angle thread rolling machine a thread rolling die I3 is placed on the middle spindle 20 with its middle keyway in alignment with the keyseat 23 and locked thereon by means of the key 43. The thread rolling die I2 is then placed on the left-hand spindle IS with its left-hand keyway 40 in alignment with the keyseat 22 and locked thereon by a key 44.

The thread rolling die I4 is then placed on the right-hand spindle 2| with its right-hand keyway '42 in alignmentwith the :keyseat 24 and locked with the key 45. The thread rolling dies are now located on the spindles in the correct angular relation to one another to assure the proper phasing of the threads at the incommensurable thread that in the illustration given by Figure 1 the threadrolling point of contact such as shownby' it, is at a point midway between thethread starts I '48 and 41 on the die it and that the distance on the circumference between the thread start Bto be, formed on the work II, and the thread roiling point of contact I! is equal to the distance on the circumference between the thread rolling point properly located for a predetermined incommensurable angle of thread rolling and if the incommensurable angle is changed such as by varying the diameter of the work without changing the distance between the die axes, the phase relationship between the dies is altered and the keyways must be located in different angular positions as determined by the formula previously described. However, this fact enables a minor precision adjustment of phasing to be made by slightly altering the distance between the die spindle axes to thus slightly alter the incommensurable thread rolling angle or by varying the distance from the common die axes, to the work center by a feeding means not shown. v a

When it is desired to roll difierent diameters of work it is only necessary to move the die spindles l9 and 2i away from the die spindle 20 to a position such as shown by the dotted lines in Figure 1 which will permit the work of greater diameter shown by the dotted lines tobe rolled at the same incommensurable angle shown bytthe dotted lines. Since the incommensurable angle is not changed, the angular relationship between the thread starts on the thread rolling dies and the keyways is still in correct phase relationship as determined by the 'formula; Figure 3 of the drawings shows a form of gearing which will permit the movement apart of the thread rolling spindles to vary the spacing between the spindles and thus permit therolling of diiferent sizes of work diameters at the sam incommensurable thread rolling angle.

Thus far, I have described an improved fo of die spindle and circular thread rolling die pro- ",vided with keyseats and keyways which will en- 'able accurate and interchangeable attachment of the dies to the spindles in the proper angular relationship to assure correct phasing of thethreads on the dies at the points of thread rolling contact. In the threespindle machine, each die \has been provided with three keyways angularly used to locate the keyways and this invention is not intended to be limited to a three spindle incommensurable angle thread rolling machine.

Referring to Figure 2 of the drawings, 'a simplifled form of the invention is shown as applied to a more conventional type of thread rolling machine in which the incommensurable angle thread rolling is not used. In this 'type of ma-' chine, the thread rolling blanks 50 and ii are located with their centers in the common plane i 6 I passing through. the centers of the spindles l2, ",and II. Keyed on the spindles are the circular thread rolling dies 65,", and II." In

this conventional type of thread rolling the interchangeable dies are each provided with only one kevway 58 located in a predetermined angular relation to a thread start such as in an axial plane intersecting one of the points of thread start 8!. The spindles I2, 63, and 84 are likewise provided with keyseats 60, 6| and 82 which are permanently angularly related at the time of assembly of the machine as previously described this instance, may be counterclockwise. To show that the proper phase relationship has been obtained, it may be pointed out that the distance on the circumference "between the thread start 63 of the work 52 and the point of thread-rolling contact 64 is equal to the distance on the circumferen'ce of the die 58 between the thread w start 65 and the point of thread rolling contact the three spindle machine shown by Figure 2 of the drawings.

It may be desirable to employ this invention in connection with a multiple spindle thread rolling machine in which the intermediate dies are of different, size than their associated dies. In

this instanceit is necessary to adjustthe gear ratio between the spindles in accordance with the die sizes but so long as the determined ratio is maintained constant during the operationlof the machine and assuming the keyseats on the spindles to be angularly located in predetermined relation to each other the correct phasing of the dies will be obtained by observing the principles curatelylocating the correct angular relationship of this invention.- a

-'Ihis invention has disclosed ameans of acthe die spindles to obtain correct phasing.

From the foregoing description of an embodiment of this invention, it should be evident to those skilled in the art that various changes and modifications might be made without departing .from the spirit or scope of this invention.

I claim:

' interchangeably applied to the spindles'of an incommensurable angle thread rolling machine,

of keyways positioned therein in predetermined angular relations to a thread start, whereby said die may be interchangeably keyed to each one of said spindles in a predetermined angular relaaciaaiv tion to said thread start to assure proper phasing of the dies ,on the machine. ,7

2. A-circular-thread rolling die adapted to be interchangeably applied to the. spindles of wincommensurable angle thread rolling machine, said die having a spindle receiving bore therethrough andat least one thread start on its threaded periphery, said bore having a plurality of keyways positioned therein in predetermined angular relations to a thread start, one of said keyways being angularly located in relation to a thread start, the others-of said keyways being angularly displaced in relation to said first mentioned keyway by an amount which isa function of the incommensurable thread rolling angle and the number of thread starts on the die, whereby said die may be interchangeably keyed to each one of said-spindles in the predetermined angular relation to said thread start to assure proper phasing'of the dies on the machine.

3. A circular thread rolling die adapted to be f interchangeably applied to the spindles oi an incommensurably angle thread rolling machine,

said die having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways positioned therein in predetermined angular relations to a thread start, one of said keyways being angularly located in relation to a thread start, the others of said keyways being angularly displaced in relation to said first mentioned keyway and each other, the angular dlsplacement in degrees being equal to the sum of twice the incommensurable thread rolling angle in degrees plus twice the incommensurable angle divided by the number of thread starts on the die, whereby said die may be interchangeably keyed to each one of said spindles in the prebore having a plurality of keyways positioned said spindles together in constant ratio, said gearing being connected to the spindles with the keyseat of each spindle in parallel axial planes to each other, a circular thread rolling die adapted to be detachably attached to each oiv said spindles, said die having a spindle receiving bore therethrough and at least one thread starton its threaded periphery, said bore having a plurality of keyways positioned therein in predetermined angular relations to a thread start," one of said keyways being angularly located in relation to a thread start, the others of said keyways being angularly displaced in relation to said first mentioned keyway and each other-by an amount which is a function of the incommensurable thread rolling angle and the number of thread starts on the die whereby the thread rolling die may be interchangeably keyed to each spindle and spindle keyseat at a predetermined angular relation to a thread start.

'7. In combination, an incommensurable angle thread rolling machine having a, plurality of spindles for receiving thread rolling dies, said spindles located in said machine with their axes in a determined angular relation to said thread start to assure proper phasing of the dies on the machine.

' 4. A circular thread rolling die adapted to be interchangeably applied to the spindles of an incommon plane, each of said spindles having a keyseat thereon, gearing revolubly connecting said spindles together in constant ratio, said gearing being connected to the spindles with the keyseat of each spindle in parallel axial planes to commensurable angle thread rolling machine,

said die having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways positioned therein in predetermined angular relations to a thread start, the number of keyways in said bore being equal to the number of spindles in the thread rolling machine, oneof said keyways being angularly located in relation to a thread start, the others of said keyways being. displaced in relation to said first mentioned keyway and each other, the angular displacement in degrees being equal to the sum of twice the incommensurable thread rolling angle in degrees plus twice the incommensurable angle divided by, the number of thread starts on the die, where-' by said die may be interchangeably keyed to each one of'said spindles in the predetermined angular I 1 ing revolubly. connecting said spindles together in constant ratio, said gearing being connected to the spindles with the keyseat of each spindle in parallel axial planes to each other, a circular "thread rolling die'adaptedto be detachably attached to each of said spindles, said die having -a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said.

each other, a circular thread rolling die adapted to be detachably attached to each of said spindles, said die having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality oi keyways positioned therein in predetermined angular relations to a thread start, the number of said keyways being equal to the number of said spindles, one, of said keyways being angularly located in relation to a thread start, the others of said keyways being angularly displaced in relation to said first mentioned keyway and each other by an amount which is a function of the incommensurable thread rolling angle and the number of thread starts on the die whereby the thread rolling die may-fbe interchangeably keyed to each spindle and spindle keyseat at a predetermined angular relation to a thread start.

8. In combination, an incommensurable angle thread rolling machine having a plurality of spindles for receiving thread rolling dies, said spindles located in said machine with their axes in a commonplane, each of said spindles having a. keyseat thereon, gearing revolubly connecting said spindles together in constant ratio, said gearing being connected-to the spindles with the keyseatof each spindlein'parallel axial planes to each other, a circular thread rolling die adapted to be detachably attached to each of said spindles, said die having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keywayspositioned therein in predetermined angular relations to a thread start, one of said keyways being angularly located in relationto a in degrees plus twice theincommensurable angle divided by the number of thread starts on the die,

whereby the thread rolling die may be interchangeably. keyed to eachspindle and spindle keyseat at a-predetermined angular relation to a thread start.

9. In combination, thread rollingmachine having a plurality of spindles for receiving threadlrolling dies, said spindles located in said machinewith their axes in a common plane, each of said spindles having a keyseat thereon, gearing revolubly connecting said spindles together inconstant ratio, said gearing being connected to the spindles with the keyseat of "each spindle in parallelaxial planes .to each other, a circular threadrolling die adapted to be detachably attached to each of said spindles, said die having a spindle receiving here therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways positioned therein i predetermined angular relations to a thread start, the number of said keyways being equal to the number of said spindles, one of said keyways being angularly located in relation to a thread start, the others of said keyways being angularly displaced in relaan incommensurable angle tion to said first mentioned keyway and each I other, th angular displacement in degrees being 1o number of thread rolling dies being eq al to the number or spindles, each or said dies having a spindle receiving'bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways therein, the 1 number of said keyways being equal to the number of said spindles, one oi'jsaid keyways being angularly-located in relation to a thread start,

the others of said keyways being angularly dls- Dlaced'in relation to said first mentioned kcyway and eachfother byan amount which is the' 1 function of the incommensurable thread rolling angle and the number of thread starts on the die, and each of said keyways adapted to cooperate V witha specified spindle keyseat whereby each of the dies'm'ay be interchangeably located on each or the spindles in the'proper angular relation between the keyseat and the thread start to assure accurate phasing of the dies. T

12. In combination, an incommensurable angle thread rolling machine having a plurality of spindles Iorreceiving thread rolling dies, each or said spindles having a keyseat thereon, gearing the number of spindles, each of said dies having 7 a spindle receiving bore therethrough and! at ,least one thread start on its threaded periphery,

said bore having a plurality of keyways therein, the number of said keyways being equal to the number of said spindles, one of said keyways being angularly located in relation to a thread I start, the others of said keyways being angurolling die may be interchangeably keyed to each spindle and spindle keyseat at a predetermined angularv relation to a thread start.

10. In combination, an incommensurable angle thread rolling machine having a plurality of spindles for receiving thread rolling dies, each of said spindles having a keyseat thereon, gearing revolubly connecting said spindles together in constant ratio, said gearing being, connected to said spindles with the keyseat of each spindle located in-parallel axial planes to each other, a plurality of thread rolling dies adapted to be interchangeably attached to each of said spindles, the number of thread rolling dies being equal to the number of spindles, each of said dies having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways therein, the number of said keyways being equal to the number of said spindleseach of said keyways being angularly locatedin relation to a thread start, and each-of said keyways adapted to cooperate with a specified spindle keyseat whereby each of the dies may be interchangeably located on each of the spindles in the proper angular relation between the keyseat and thread start to assure accurate phasing of the dies.

11. In combination, an incommensurable angle thread rolling machine having a plurality of spindles for receiving thread rolling dies, each of said spindles having a keyseat thereon, gearing revolubly connecting said spindles together in constant ratio, said gearing being connectedto said spindles withthe keyseat of each spindle located inpa'rallel axial planes to each other, a plu-.

larly displaced from said first mentioned keyway and each other, the angular displacement, in degrees being equal to the sum of twice the incommensurable thread rolling angle in degrees plus twice the incommensurable angle divided by the number of thread starts on the die, and each of said keyways adapted to cooperate with a specified spindle keyseat whereby each of the dies may be'interchangeably located on each of the spindles in the proper angular relation between the keyseat and thread start to assure accurate phasing of the dies.

13. In combination, an incommensurable angle thread rolling machine having a plurality of spindles for receiving thread rolling dies, each of said spindles having a keyseat thereon, gearthe number of thread rolling dies being equal to the number of spindles, each or said dies having a spindle receiving bore therethrough and at leastone thread start on its threaded periphery, said bore having a plurallty of keywaystherein, the number of said keyways being equal to the nrumbar of said spindles, one of said keyways being angularly locatedin relation to a thread start, A

the others of said keyways being angularly dislaced in relation to said first mentioned keyway and each other by an amount which is the iuncindigaatethe correct keyway to cooperate with a specified spindle keyseat, wherebyeach of the dies may be interchangeably located on each or the rolling angle in degrees plus twicethe incommensur'able angledivided by the numberoi thread starts on the die, each orsaid keyways adapted to spindles in the proper angular relation between ably attached to each of said spindles, the num- 7 her of thread rolling dies being equal to the number of spindles, each of said dies having a spindle receiving bore therethrough and at least one thread start on its threaded periphery, said bore having a plurality of keyways therein, the number oi! said keyways beinB equal to the number or said spindles, one of said keyways being angularly located in relation to a thread start, the others or said keyways being angularlydisplaced from said first mentioned keyway and each other, the angular displacement in degrees being equal to the sum of twice the incommensurable thread cooperate with-a specifledspindle keyseat, means. .on the die to indicate the correctlkeyway tOTOOOD-Lr vcrate with a specified spindlekeyseat, whereby each of the dies maybe interchangeably located on each of the spindles in the proper angular relation between the'keyseat and" thread 'start'to sure accurate phasing of the dies. I JAMES W.-BATCH.ELDER.- anr'lh cl-is The following references are of record in the tile of this patent:

' UNITED STATES PATENTS Number i Name Date 302,600 Stetson Ju1y 29, 1884 622,475 Hubbell Apr. 4, 1899 1,496,116 Browne June 3, 1924 2,252,130 Lamprecht Aug. 12, 1941 2.257,234 Gould -....-I. Sept, 30, 1941 FOREIGN PATENTS Number Country Date British Jan. 11 1895 

